Antiviral agents used against human herpesvirus and influenza virus infections

Background: Antiviral agents and vaccines are practical tools used against many viral diseases. This review focuses on the antiviral agents used against human herpesviruses and influenza viruses, which are frequently encountered in clinical practices.Current Concepts: Recently developed antiviral agents mostly target human immunodeficiency viruses or hepatitis viruses. As most viruses invade host cells and use host metabolic systems for replication, it is difficult to develop novel antiviral agents.Discussion and Conclusion: Diseases, pathogenesis, indications, and dosages of antiviral agents used to combat herpes simplex virus (HSV), varicella-zoster virus (VZV), and cytomegalovirus (CMV) are described as most of these viruses require treatment. Acyclovir, valacyclovir, and famciclovir are frequently used against HSV and VZV in Korea. Ganciclovir and valganciclovir are frequently used against CMV; foscarnet, cidofovir, and maribavir are used in refractory cases. Drugs currently used for influenza virus infections and recently introduced drugs such as oseltamivir, peramivir, zanamivir, and baloxavir marboxil are also included in this review. Clinicians should keep abreast of continued developments in antiviral agents and correct usage of drugs to overcome viral diseases.